Abstract:
The precipitation behavior of nitride precipitates in grain-oriented silicon steel containing vanadium and titanium elements produced by thin slab casting and rolling process was studied by thermodynamic calculation and simulation experiment. The feasibility of nitride precipitates containing V and Ti elements as auxiliary inhibitors was also investigated. It is found that TiN is likely to precipitate at the final stage of solidification in the grain-oriented silicon steel, but VN and AlN can precipitate only in the two-phase region after solidification. Nitride precipitates in the grain-oriented silicon steel are mostly compound precipitates with complex chemical composition. Meanwhile, with increasing V and Ti contents, the distribution density of total inhibitors is significantly improved due to the increase in amount of nitride precipitates containing V and Ti elements. The inhibiting ability of inhibitors which restrain the normal growth of primary recrystallization grains is strengthened, and the magnetic induction value of final product is upgraded from 1.857 T to 1.898 T. Moreover, the addition amount of V and Ti, which is not more than 0.005% and 0.007%, respectively, does not affect the decarburization effect and the removal of S and N elements; the formed nano-sized nitride precipitates containing V and Ti elements are suitable as auxiliary inhibitors in the grain-oriented silicon steel produced by thin slab casting and rolling process.